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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>
    <script>
        // 1.0 实例化
        let formData = new FormData();

        // 2.0 追加数据
        formData.append('name', '程咬金');
        formData.append('age', 2000);

        // 3.0 遍历打印出来查看是否追加成功
        formData.forEach(function (value, key) {
            console.log(key,value)
        })

    </script>

</body>

</html>